Control mechanism for internal combustion engines



April 1942- FOG. FOLBERTH arm. I 2,278,871

CONTROL MECHANISM FOR INTERNAL COMBUSTION ENGINES Filed July 7, 1935 2 Sheets-Sheet 1 a /5 67 66 63 60 6/ ZSnnentors WQM (Ittomegs April 1942- F. e. FOLBERTH ETAL 2,273,871

CONTROL MECHANISM FOR mwmamucomusnon suenms Filed July '7, 19:53 2 Sheets-Sheet 2 WIN I 1 a FEEDE/P/Ck 6. P0135271? w/u IAM M FOLBZ-PTH Junentors inserted in the air inlet to the carburetor.

Patented Apr. 7, 1942 CONTROL MECHANISM FOR INTERNAL COMBUSTION ENGINES Frederick G. Folberth and William M. Folberth,

Cleveland, Ohio Application July *7, 1983, Serial No. 679,368 6 Claims. (01. 123-119) This inventionrelates to control mechanism and more particularly to means for controlling the mixture of air and gasoline or other fuel sup- "plied to an internal combustion engine.

In internal combustion engines of the typev commonly used in automobiles and other automotive vehicles a carburetor is utilized to mix the gasoline'or other liquid fuel with air to form an explosive mixture, which mixture is then conducted to the cylinders of the engine. A throttle valve may be interposed in the mixture passage between the carburetor and the engine cylinders and a so-called choke valve is Also, in present day automotive engines, it is common practice to provide a thermostatically actuated and controlled valve in the water passage which leads from the water jacket of the engine cylinders to the radiator. The object of this thermostatically controlled valve is to prevent or retard the circulation of water through the radiator until the engine has reached the proper operating temperature. Thus, the valve is normal .ly maintained in closed position by the thermostatic element when the water temperature is below a certain predetermined value. As the water in the water jackets of the engine is heated, due to the travel of heat thereto through the cylinder walls, the thermostatic element acts to open the water flow control valve and permit circulation of the water through the radiator where it is cooled to the desired lower temperature before being returned to the engine.

In our present invention we have provided means for interconnecting the thermostatic water control valve and the choke valve whereby,

when the engine is cold and the water valve is in its closed position, the choke valve may be manually moved into its completely closed position but whereby, when the engine is warm and the water valve is in its open position, the choke valve cannot be closed more than a predetermined amount. Associated with and controlled by the water valve mechanism we have provided an auxiliary gasoline valve which is adapted to be opened when the water valve is closed and the engine is cold and to be automatically closed when the water valve is open and the engine is at normal operating temperature.

The manipulation of the choke valve of an automobile engine has always caused the ordinary driver considerable difliculty and it is among the objects of our invention to provide means for making it impossible for the vehicle driver to improperly operate the choke valve.

Other objects of our invention are the provision of a fuel supply control device for internal combustion engines by which the quantity or the richness of the explosive mixture fed to the engine is varied according to the operating temperature of the engine; the provision of means for supplying an extra amount of fuel to the engine when the engine is cold and automatically shutting off the extra fuel supply when the engine reaches operating temperature; the provision of a control mechanism in which an auxiliary fuel supply, the movement of'the choke valve and the circulation of the cooli g Water through the radiator are automatically Controlled in accordance with the operating temperature of the engine; the provision of means for increasing the quantity of fuel supplied to the engine when it is started from cold condition whereby the richness of the mixture is increased and it is therefore unnecessary to materially restrict the air inlet by means of a choke valve as would ordinarily be the case.

The above and other objects of our invention will appear from the following description of several embodiments thereof, reference being had to the accompanying drawings, in which- Figure 1 is a fragmentary side elevation of an automobile internal combustion engine illustrating our control mechanism with the parts thereof in the positions assumed when the engine is cold and the choke valve has been manually closed by the operator.

Figure 2 isan enlarged fragmentary view of the carburetor and operating linkage illustrated in Figure 1 showing the parts in the same posi tions as in Figure 1.

Figure 3 is an enlarged vertical cross section taken through the water outlet from the engine and illustrating the thermostatically controlled water valve of Figure 1.

Figure 4 is a detached plan view of the water valve shown in Figure 3.

Figure 5 is an enlarged cross section taken on line 5-5 of Figure 4 and illustrating the relief valve which is associated with the water control valve.

Figure 6 is a vertical cross section, generally similar to Figure 3, but illustrating a modified form of water valve and thermostatic element.

Figure '7 is a side elevation, partly in section,

, of a carburetor equipped with our automatic control mechanism and including automatic choke valve operating means.

Figure 8 is an enlarged view of the connection between members "I9 and 85 of Figure 7.

Referring now to Figure 1, the engine cylinder block I is provided with a cylinder head portion la on which is formed a boss 2 to which is secured the cooling water outlet pipe 3. As is well understood by those skilled in the art, this cooling water outlet pipe 3 is connected by a suitable hose or conduit to the vehicle radiator (not shown) and the cooling water may be returned to the lower part of the engine block from the radiator through another conduit (not shown). The intake manifold 4 is provided with a riser portion 5 which is connected to the up wardly extending throat 6 of the carburetor C. A throttle valve 6' is disposed in the throat ii. The carburetor C is also provided with a horizontally extending air inlet portion I in which is disposed the butterfly type of choke valve 8. A float chamber 9, of any suitable and well known type, is associated with the carburetor C and contains a float and float operated valve (not shown) which is adapted to maintain the level of the fuel in the float chamber at the proper point to provide a steady supply of fuel to the carburetor nozzle 9a.

The cooling water control valve V, together with the thermostatic element T, is disposed within the water outlet pipe 3, as is best seen in Figure 3, and as will be more fully described later. This valve V is of the butterfly type and is mounted on a shaft I0, one end of which extends out through suitable packing (not shown) in the wall of the outlet pipe 3. A lever II is secured to the outwardly extending end of the shaft l and is connected by the link or rod Ha to the upper end |2 of the auxiliary fuel valve operating lever. This fuel valve operating lever is rotatively mounted on a pin I3 which extends out from the side of the carburetor C and the lower end Id of the lever is connected to the needle type of auxiliary fuel valve l as will be described in detail later.

One end of the choke valve control link L is connected to the fuel valve operating lever at a point intermediate the pivot point l3 and the pivoted connection between the rod Ila and the upper end portion l2 of said fuel valve operating lever. The other end of this link L is connected to a bell crank lever |6-|8 one arm I6 of which is secured to the choke valve shaft I! (see Figure 2). The manual choke operating lever arm I8 is also secured to the shaft I! and is connected by the rod l9 to the choke operating button which is preferably on the dash board of the vehicle. Interposed in the rod I9 is a spring 2|,

the purpose of which will be later described. A r

spring 22, weaker than spring 2| however, is attached at one end to the rod I9 and at its opposite end to the cylinder block I or other suitable fixed point. This spring 22 normally maintains the choke valve 8 in its horizontal or wide open position. It will be seen, however, that when the operator pulls out on the button 20 the choke valve 8 will be moved toward its closed position, the movement of the button 20 being; transmitted through the spring 2| which is stronger than the spring 22. When the operator releases the button 20 the spring 22 will immediately return the choke valve 8 to wide open position.

One form of our improved cooling water con- Disposed within the pipe 3 is ill) the thermostatic element T which, as illustrated in Figure 4, comprises a spirally wound bi-metallic strip 23 made up of two metals having different coefficients of expansion. The inner end of this spiral strip 23 is secured to a pin 24 which in turn is attached to the pipe 3. The outer end 23' of the thermostatic element is attached to the lower end of the connecting rod 25, the upper end of which extends through an aperture 26 in the body of the valve V and is pivotally connected at its upper end to the cap member 21 which covers the aperture 26 and prevents the flow of cooling fluid therethrough. As is best seen in Figures 4 and 5 this cap member 21 is preferably a flanged stamping which is soldered or otherwise secured to the valve V and which is provided with a transverse pin 28 to which the connecting rod is pivotally secured. The valve V is a substantially circular disc member which is secured to the transverse shaft l0. One end of this shaft ID has a bearing in a suitable aperture in the pipe 3 and the other end of the shaft l0 extends out through the wall of the pipe 3 and carries the lever I. It will be understood that the pipe 3 will be so constructed that the valve V may be readily installed in its operating position and that suitable packing will be provided around the shaft I0 where it extends out through the wall of the pipe I I so that leakage of cooling water will be prevented.

Auxiliary pressure relief valve means are incorporated in the valve V. This pressure relief device comprises a disc 29 which is normally seated on the upper side of the valve V and covers and closes the apertures 30. A headed pin 3| extends upwardly from the valve V and a spring 32, normally under compression, has its opposite ends seated against the head of the pin 3| and the disc 29 respectively. The lower end of the pin 3| is preferably soldered or otherwise secured to the valve V so that there will be no leakage between the pin and the valve. As the disc 29 is adapted to slide on the pin 3|, it will be seen that if the pressure of the water against the underside of the disc 29 becomes great enough to overcome'the spring 32, the disc 29 will be lifted from its seat and water will flow through the holes 30 thus relieving the pressure against the main cooling water control valve V.

When the engine is cold and the cooling water in the cylinder jacket and in the pipe 3 is also relatively cold the valve V will be in the position shown in Figures 1 and .3. As the cooling water is heated after the engine is started the thermostatic element T will coil up into a tighter spiral due to the increase in temperature and this will exert a force through the connecting rod 25 to open the valve V and permit a greater flow of cooling water from the engine water jackets to the radiator. The thermostatic elements and the other parts may be so designed that, when the proper operating temperature is reached, the valve V will be in its wide open position but as long as the engine is below the predetermined proper operating temperature the flow of cooling water to the radiator will be retarded.

It will be understood that types of thermostatic valve operating elements other than that illustrated may be used and that the coil 23 or other type of thermostatic unit will be made of the proper size and materials to give the desired control of the water circulation, the choke valve, and auxiliary fuel valve. For example, the well known bellows type of thermostatic operating element may be utilized as is illustrated in Figure 7.

In this view the thermostatic elei'nent.v 35 con-- sists of a'metallic bellows having a volatile fluid to a perforated bracket 36 by the nut 31 and has a rod 38 projecting upwardlyfrom its upper end. The poppet valve 39 is adapted to seat upon the flange 4c and is provided with a downwardly extending tubular member 4| in which the rod 38 has a sliding fit. It will be noted that the member 4| is slotted at 42 and a pin 43, which is secured to the rod 38, projects into this slot 42. A valve stem 44 is secured to the valve 39 and extends 1 'The arm 52 of the bell crank is made of proper length to give the desired movement to a rod 52' which is connected to the outer end of lever arm 52 and which will operate in the same manner as and perform the same functions as the rod Ha shown in Figures 1 and 2.

The operation of the apparatus shown in Figure 6 is as follows:

When the parts are in the positions illustrated the engine may be considered to be cold, or below the proper operating temperature. The valve 39 is seated upon its seat 40 and the flow of cooling water to the radiator of the vehicle is retarded. It will be understood that, if desired, a pressure relief valve such as shown in Figure may be mounted on the valve 39. As the thermostatic element 35 is surrounded by cooling water it will respond to the temperature thereof and when the cooling water temperature rises to a predetermined point the fluid within the element 35 will expand or vaporize causing the bellows to expand. This movement will be transmitted through the pin 43- to the valve 39 and will lift the valve off its seat permitting the cooling water to fiow through the pipe 5| into the radiator. A coil spring 54, normally under'compression, is disposed between the valve 39 and the lower end of the sleeve member 45 and exerts a force tending to hold the valve 39 in closed position. When the temperature of the cooling fluid goes below the predetermined value the bellows 35 will contract and this action, together with the action of the spring 54, will return the valve .39 to its seat; 4%) and again shut oif or retard the circulation of the cooling fluid. The upward movement of the valve 39, which occurs when the thermostatic element 35 expands, will be transmitted through the valve stem 44 to the bell crank lever 48-452 which is pivoted to the bracket 50 at 49. This will cause the arm 52 of the bell crank lever 4852 to move in the direction of the arrow (Figure 7) and the rod 52' will be moved in the same manner as the rod Il a when the arrangement of Figures 1 and 4 is used.

Returning now to Figure 2, the lower end 14 of the auxiliary fuel valve operating lever is provided with a forked end portion I 4 which fits around the auxiliary needle valve stem 56. A head 51 is formed on the upper end of the stem '56 and is adapted to be engaged by the forked end of the lever arm [4. The valve stem 56 extends downwardly through suitable packing 5B and isprovided with a. flange 59 intermediate its ends. The lower end of the stem 56 is tapered as shown at to and is adapted.- to be seated in a cone shaped enlargement 6| of the fuel by-pass passage 62. A spring 63 is disposed between the bottom surface of the packing gland 64 and the flange 59 and exerts a force tending to maintain the needle valve 60 seated upon its seat 6]. The main fuel supply from the fluid chamber 9 to the nozzle 9a includes the passage 65, the jet 66 and the chamber-6T. The auxiliary fuel supply to the nozzle 9a. is provided through the passage 62, around the needle valve 60 and through the passage '68 to the chamber '61.

Itwill be noted from Figure 2 that the link L, which joins the lever arm I 2 of the auxiliary fuel supply lever and'the choke valve lever arm l6, includes a rod portion 10 having a plunger member H secured to its lower end and a tubular section 1 2which is 'pivotally secured to the lever arm i6 and which has a reduced portion 13 which forms a guide and bearing for the rod NJ. The function of the link L is to provide means for restricting the degree of movement of the choke valve 8 in closing direction in accordance with the operating temperature of the vehicle engine and its action will be more fully described later.

Referring now to Figure 1, it may be assumed that the vehicle engine is cold and that the oporator, in preparation for starting the engine, has

by the link L.

Now let us assume that the operator has started the vehicle engine and has released the button 20 whereupon the spring 22, or other suitable choke valve opening means, has moved the choke valve 8 into its wide open position. However, the engine is still receiving an extra or greater than normal supply of gasoline through the bypass 62 around the open needle valve'6fl and the passage 68 which leads into the chamber 61. Thus, even though the engine is cold it will function properly because of the rich mixture of fuel and air which is supplied to the cylinders. It will be noted that this rich mixture is obtained without the use of the usual choke valve and in fact, with our apparatus, the choke valve need not be used except during the initial cranking and starting of a very cold engine in order to draw a very rich supply of fuel into the cylinders. As the choke valve 8 is opened as soon as the button '20 is released by the operator it cannot accidentally be left in closed position thus flooding the engine and causing improper operation. After the engine has been running a certain time the cooling fluid in the cylinder jackets will be heated to the temperature required to actuate either the thermostatic device '23 or 35. When this temperature is reached these elements will act to open the water circulation con trol valve and permit the cooling water to flow through the radiator and also to move either the rod Ila or the rod 52 upwardly (in the direction of the arrow in Figure 2). This upward movement of the rod Ila or 52' will cause a corresponding downward movement of the forked end M of the lever arm M and the spring 63 will then act to move the needle valve stem 56 downwardly until the pointed needle valve 60 is seated in its seat 6| thereby closing off the auxiliary fuel supply. Thus, when the engine temperature reaches the proper operating point the auxiliary fuel supply will be automatically shut off, as under these conditions it will not be needed.

When either rod Ha or 52 moves upwardly as above described the lever arm l2 will also move upwardly and will carry with it the rod I and the head or plunger Thus, if the choke valve is open/the distance between the plunger 7| and the reduced portion 13 of the tubular member 12 will be decreased. The efiect of this will be to reduce the angle through which the choke valve 8 may be moved in closing direction. Moreover, if the choke valve should be in closed position when this movement of the arm l2 occurs it will be positively moved in opening direction and the choking action thereby reduced.

It will be seen from the above description that when the engine has reached the proper operating temperature the auxiliary fuel supply will be.

closed and, through the link L, the movement of the choke valve 8 will be so limited that it cannot be moved into fully closed position. This is a desirable feature as, when the engine has reached the proper operating temperature, it is never desirable nor proper to fully choke the air supply to the carburetor. The spring 2| (Figure 1), which is inserted in the choke valve operating member I9, is for safety purposes in order to prevent the vehicle operator from imposing too severe a strain upon the link L and the auxiliary fuel supply mechanism. If the cooling fluid control valve is open the plunger ll of the member 18 of the link L will have been moved from the position of Figure 2, upwardly. Now if the choke valve 8 is in open position and the' operator desires to choke the air supply he may do so by pulling on the button 28. However, as soon as the plunger H engages the reduced portion 13 of the tubular member 12 further movement of the choke valve 8 in closing direction will be prevented. However, should the operator inadvertently continue to pull on the choke button he will merely extend the spring 2| and will not damage the other parts of the mechanism.

In Figure '7 we have illustrated a modified form of our invention in which the choke valve is automatically controlled by the pressure in the intake manifold or other part of the conduit which conducts the mixture from the carburetor.

Although the cylinder 15 is shown mounted on the body of the carburetor it will be understood that it might be mounted directly on the intake manifold without changing its function or mode of operation. A piston 11 is disposed within the cylinder 15 and the piston rod 18 extends out through and has a bearing in the end cap 19 of the cylinder 15. A spring 80 is disposed between the piston and the wall of the riser I6 and is normally under compression and exerts a. force tending to move the piston 11 to the left. A small bleeder hole 8| extends through the wall of the riser 16 and connects the interiorof.

cylinders.

the cylinder 15 with the interior of the riser 16 at a point between the throttle valve 82 and the engine cylinders. The opposite end of the cylinder 15 is connected to the atmosphere through a small bleeder hole 83.

Mounted .on the end cap 18 of the cylinder 15 is an outwardly extending bracket 84 on which is pivotally mounted a bell crank lever, one arm, 85, of which extends upwardly and has a slotted joint connection J with the end of the piston rod 18 and the other arm, 86, of which extends outwardly at approximately 90 to the arm 85.

The choke valve 8' is substantially the same as the choke valve 8 shown in Figure 2 and the lever arm "5', link L, lever arms l2 and Ma, auxiliary fuel valve stem 56 and operating rod lib are all disposed in the same manner and operate in the same way as the corresponding .parts shown in Figure 2. Secured to the shaft H, which carries the choke valve 8, is a lever arm 81 and a rod or link member 88 connects the outer end of this lever arm 81 with the outer end of the lever arm 86.

When the engine to which the apparatus of Figure '7 is attached is not running atmospheric pressure will exist within the riser 16. Therefore both sides of the piston Tl will be subjected to atmospheric pressure and the spring 88 will move the piston T! to the left into the position shown in Figure '7. This movement of the piston 11 causes the bell crank lever to swing about its pivot point on the bracket 81 and to move the rod 88 downwardly thus moving the choke valve 8 into its closed position, as illustrated. Thus, when the vehicle engine is started, the choke valve will be closed and a relatively rich mixture will be fed to the engine As soon as the engine begins to operate, however, the pressure Within the riser I6 adjacent the bleeder hole 8| will be reduced and air will be withdrawn from. the right hand end of the cylinder 15 through the bleeder hole 8|. When a suflicient pressure differential is established between the opposite sides of the piston 11 the spring will be overcome by the atmospheric pressure and the piston 11 will be moved to the right. This movement will cause the arm 86 of the bell crank lever to move upwardly in the direction of the arrow, which movement will be transmitted through the link 88 to the lever 81 which will likewise move upwardly. This movement of the lever 81 will cause the choke valve 8' to move in opening direction (indicated by the dotted arrow in Figure 8) and the parts will preferably be so proportioned that, when the piston 11 reaches the end of its movement towards the riser 16, the choke valve 8' will be in its horizontal or fully opened position.

By making the bleeder holes 8| and 83 relatively small the reduction of pressure within the riser 16 upon starting the engine will not immediately be eifective to cause movement of the piston 11. By properly proportioning the size of the openings 8| and 83 the spring 80 and the size of the cylinder 15, etc., the time during which the choke valve 8' will remain closed after the engine has started may be controlled.

By connecting the above described automatic choke valve operating mechanism with our temperature controlled choke valve regulating means a very simple control system is provided. If the engine is absolutely cold when started the link L will be in a position to permit full closing of the choke valve 8' and thus the full choking action can be secured. However, if the engine is at its operating temperature and the thermostatically controlled water valve V or 35 is open, the link L Will be positioned to prevent the full closing of the choke valve 8' and over-choking of the engine by the action of the spring 80 and the connecting linkage will be prevented. Thus the automaticchoke operating means and the temperature controlled choke regulating device coact with the auxiliary fuel supply to provide an effective automatic control mechanism.

From the above description of the operation of our apparatus it will be seen that we have provided automatic means for supplying an additional amount of fuel to the engine until it has reached the proper operating temperature. Our apparatus is also adapted to automatically open the choke valve upon the engine reaching proper operating temperature, provided the operator has neglected to so open the choke valve. Further, with our apparatus, the operator is prevented from fully choking the engine when, it is warm and thus harmful flooding is prevented. By interconnecting the auxiliary fuel supply control valve and the thermostatic element which concombustion engine, and as the operation of this I portion of our apparatus is entirely automatic, the human element is eliminated and much more satisfactory operation may be obtained. With the apparatus of Figure 7 an automatic choke valve operating device is provided and interconnected with our choke regulating apparatus whereby the manual operation of the choke valve upon starting the engine may be eliminated.

Although we have described in considerable detail the illustrated embodiments of our invention, it will be understood by those skilled in the art that modifications and variations in the specific arrangement of parts and details of the apparatus may be made without departing from the spirit of our invention. We do not there fore, wish to be limited to the particular form herein described and illustrated but claim as our invention all embodiments thereof coming Within the scope of the appended claims.

We claim:

1. In combination with an internal combustion engine, a carburetor having a choke valve and a fuel nozzle, means responsive to the operating temperature of the engine for varying the quantity of fuel supplied to said nozzle and means operated by said temperature responsive'means for limiting the movement of said choke valve in closing direction, said movement limiting means comprising a sliding link member having one part connected to be moved by said temperature responsive means, another part adapted to move with said choke valve and means for limiting the relative movement of said parts.

2. In combination with an internal combustion engine, a carburetor having a choke valve and a fuel nozzle, means, responsive to the operating temperature of the engine, for varying the quantity of fuelsupplied to said nozzle, means responsive to an engine function for moving said choke valve in closing direction when the engine is stopped and opening said choke valve when the engine is running, and means operated by said temperature responsive means for limiting the movement of said choke valve in closing direccarburetor, manually operable means for moving said choke valve in closing direction, means tending to hold said choke valve in open position at all times, and means, responsive to the operating temperature of said engine, for restricting the degree of closing movement only, which may be imparted to said choke valve by said manually operable means, without restricting the opening movement thereof. I

4. In combination with an internal combustion engine, a carburetor having a. choke valve and a fuel supply passage, means, responsivev to the operating temperature of the engine, for varying the quantity of fuel supplied to said fuel passage, means responsive to the pressure in the mixture conducting conduit extending from the carburetor for moving said choke valve in closing direction when the engine is stopped and opening said choke valve when the engine is runflow control means to increase or decrease the I quantity of fuel supplied to said fuel passage,

and means operated by said temperature responsive means for limiting the movement of said choke valve in closing direction.

6. In combination with an internal combustion engine, a carburetor having a choke valve and a fuel supply passage, means responsive to e the operating temperature of said engine for varying the quantity of fuel supplied to said passage and means operated by said temperature responsive means for limiting the movement of said choke valve in closing direction, said movement limiting means including a slip joint connection having one part connected to be moved by said temperature responsive means, another part adapted to move with said choke valve, and means for limiting the relative movement of said parts.

FREDERICK G. FOLBERTH. WILLIAM M. FOLBERTH. 

